학술논문
Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Transmission Spectroscopy
Document Type
article
Author
Masayuki Kuzuhara; Akihiko Fukui; John H. Livingston; José A. Caballero; Jerome P. de Leon; Teruyuki Hirano; Yui Kasagi; Felipe Murgas; Norio Narita; Masashi Omiya; Jaume Orell-Miquel; Enric Palle; Quentin Changeat; Emma Esparza-Borges; Hiroki Harakawa; Coel Hellier; Yasunori Hori; Kai Ikuta; Hiroyuki Tako Ishikawa; Takanori Kodama; Takayuki Kotani; Tomoyuki Kudo; Juan C. Morales; Mayuko Mori; Evangelos Nagel; Hannu Parviainen; Volker Perdelwitz; Ansgar Reiners; Ignasi Ribas; Jorge Sanz-Forcada; Bun’ei Sato; Andreas Schweitzer; Hugo M. Tabernero; Takuya Takarada; Taichi Uyama; Noriharu Watanabe; Mathias Zechmeister; Néstor Abreu García; Wako Aoki; Charles Beichman; Víctor J. S. Béjar; Timothy D. Brandt; Yéssica Calatayud-Borras; Ilaria Carleo; David Charbonneau; Karen A. Collins; Thayne Currie; John P. Doty; Stefan Dreizler; Gareb Fernández-Rodríguez; Izuru Fukuda; Daniel Galán; Samuel Geraldía-González; Josafat González-Rodríguez; Yuya Hayashi; Christina Hedges; Thomas Henning; Klaus Hodapp; Masahiro Ikoma; Keisuke Isogai; Shane Jacobson; Markus Janson; Jon M. Jenkins; Taiki Kagetani; Eiji Kambe; Yugo Kawai; Kiyoe Kawauchi; Eiichiro Kokubo; Mihoko Konishi; Judith Korth; Vigneshwaran Krishnamurthy; Takashi Kurokawa; Nobuhiko Kusakabe; Jungmi Kwon; Andrés Laza-Ramos; Florence Libotte; Rafael Luque; Alberto Madrigal-Aguado; Yuji Matsumoto; Dimitri Mawet; Michael W. McElwain; Pedro Pablo Meni Gallardo; Giuseppe Morello; Sara Muñoz Torres; Jun Nishikawa; Stevanus K. Nugroho; Masahiro Ogihara; Alberto Peláez-Torres; David Rapetti; Manuel Sánchez-Benavente; Martin Schlecker; Sara Seager; Eugene Serabyn; Takuma Serizawa; Monika Stangret; Aoi Takahashi; Huan-Yu Teng; Motohide Tamura; Yuka Terada; Akitoshi Ueda; Tomonori Usuda; Roland Vanderspek; Sébastien Vievard; David Watanabe; Joshua N. Winn; Maria Rosa Zapatero Osorio
Source
The Astrophysical Journal Letters, Vol 967, Iss 2, p L21 (2024)
Subject
Language
English
ISSN
2041-8213
2041-8205
2041-8205
Abstract
Recent discoveries of Earth-sized planets transiting nearby M dwarfs have made it possible to characterize the atmospheres of terrestrial planets via follow-up spectroscopic observations. However, the number of such planets receiving low insolation is still small, limiting our ability to understand the diversity of the atmospheric composition and climates of temperate terrestrial planets. We report the discovery of an Earth-sized planet transiting the nearby (12 pc) inactive M3.0 dwarf Gliese 12 (TOI-6251) with an orbital period ( P _orb ) of 12.76 days. The planet, Gliese 12 b, was initially identified as a candidate with an ambiguous P _orb from TESS data. We confirmed the transit signal and P _orb using ground-based photometry with MuSCAT2 and MuSCAT3, and validated the planetary nature of the signal using high-resolution images from Gemini/NIRI and Keck/NIRC2 as well as radial velocity (RV) measurements from the InfraRed Doppler instrument on the Subaru 8.2 m telescope and from CARMENES on the CAHA 3.5 m telescope. X-ray observations with XMM-Newton showed the host star is inactive, with an X-ray-to-bolometric luminosity ratio of $\mathrm{log}{L}_{{\rm{X}}}/{L}_{\mathrm{bol}}\approx -5.7$ . Joint analysis of the light curves and RV measurements revealed that Gliese 12 b has a radius of 0.96 ± 0.05 R _⊕ , a 3 σ mass upper limit of 3.9 M _⊕ , and an equilibrium temperature of 315 ± 6 K assuming zero albedo. The transmission spectroscopy metric (TSM) value of Gliese 12 b is close to the TSM values of the TRAPPIST-1 planets, adding Gliese 12 b to the small list of potentially terrestrial, temperate planets amenable to atmospheric characterization with JWST.